The module File::Slurp provides two functions for reading and writing files
in a simple way.

Dancer is route based so you for each page out there you need to define a route.
You can even differentiate between the HTTP METHOD types such as GET and POST
though they are written in lower case in Dancer.

We changed the config.yml file in the root of the application. Commented out the

In this code the config method returns the all the configuration options
where we already saved the name of the json file.
-e $filename checks if the file exists. If it does, we read it in to the $json
variable if not then we assign to it a json string representing an empty hash.